Supporters of President Donald Trump crashed New York Mayor Bill de Blasio’s press conference touting the city’s “Green New Deal” inside the lobby of Trump Tower on Monday morning, holding signs with insults directed at the far-left Democrat.

Speaking at a podium steps from the spot where President Donald Trump announced his own presidential run in 2015, the Democrat said he had come to Trump Tower to promote a new city air pollution law requiring skyscraper owners to cut greenhouse gas emissions or face fines.

De Blasio said Trump’s buildings in the city could face a combined $2.1 million in annual fines if they don’t reduce emissions by 2030.

“President Trump, you’re on notice. Your polluting buildings are part of the problem,” he claimed.

However, de Blasio’s speech was all-but drowned out by a throng of Trump supporters who demonstrated behind him on the building’s escalators, booing, whistling, chanting and holding up signs with messages including “Failed mayor” and “Worst mayor ever.” Footage of the heckling was shared to social media.

As we await Mayor de Blasio’s presser at Trump Tower, music blares to drown him out and a LGBT for Trump supporter makes the elevator descent. pic.twitter.com/OF6LdANPLC